Door catches



y 1964 M. J. JAMES 3,133,757

DOOR CATCHES Filed Nov. 14, 1960 2 Sheets-Sheet 2 NVENTOR I/ d M ATTORNEY United States Patent 3,133,757 DOGR (IATCHES Michael Joseph James, Charlton Kings, Cheltenharn, England, assignor to Micro and Precision Mouldings (Cheltenham) Limited, Cheltenham, England Filed Nov. 14, 196i Ser. No. 69,051 Claims priority, application Great Britain Nov. 24, 1959 9 Claims. (Q1. 29275) This invention relates to door catches of the roller type in which a spring-loaded plunger carries a freely rotatable roller which engages in an aperture in a keeper plate to hold the door closed. In use a housing of the plunger is normally mounted in the edge of the door with the keeper plate fixed to the corresponding jamb post.

The object of the invention is to provide a new or improved catch of the above type which is manufactured from a resilient plastic material so as to be relatively silent in operation whilst requiring no lubrication, and in which the roller is restrained against excessive projection from its housing in a particularly simple manner.

According to the invention a roller-type door catch has a spring-loaded plunger manufactured from a resilient plastic material and formed with an abutment shoulder or shoulders to prevent excessive outward projection of the roller of the catch from a housing of the plunger, the arrangement being such that the plunger can during assembly be sprung into position in the housing through an end or guide aperture in the latter through which it normally projects.

The abutment shoulders are preferably provided on the two limbs of a forked outer end of the plunger between which the roller is mounted, and the latter may be of a plastic material such as nylon. With this arrangement the fork limbs are pressed towards each other during assembly of the catch so that the abutment shoulders clear the guide aperture, whereupon the limbs are released aud the shoulders spring into position behind the aperture to limit outward movement of the plunger.

The fork limbs may be formed with clearance relatively to the roller suificient to enable the forked end to be flexed to enable the abutment shoulders to pass through the guide aperture, in which case as described in the specification of our application Serial No. 69,052 filed November 14, 1960, the roller is conveniently mounted upon st'ub shafts integral with the plunger. Such clearance may be provided by stepping the limbs inwardly of the roller or by forming them with an internal taper. the fork limbs and be placed in position after the plunger is fitted in the housing, a separate roller pivot pin being mounted in the fork limbs.

Although the abutment shoulders prevent excessive outward projection of the roller, adjustment means are preferably provided so that a smaller normal outward projection can be obtained if desirable for satisfactory operation of the catch.

The invention will now be further described with reference to the accompanying drawings which illustrate, by way of example, a roller door catch in accordance with the invention and a slight modification thereof, and in which:

FIGURE 1 is a front view of the catch.

Alternatively, the roller may fit closely between 3,133,757,- Patented May 19, 1964 FIGURE 2 is a sectional view on the line IIII in FIGURE 1,

FIGURE 3 is a rear view of the catch,

FIGURE 4 is an overhead plan view thereof,

FIGURE 5 is a sectional view similar to FIGURE 2 but illustrating the modification,

FIGURE 6 is a front view of a keeper plate of the catch, and

FIGURE 7 is a sectional view on the line VII-VII in FIGURE 6.

The catch is manufactured substantially entirely from plastic material by injection moulding, and has a forkended plunger 1 moulded from resilient plastic material and between the similar fork limbs 2 of which a plastic roller 3 is mounted. The plunger 1 is slidably mounted within a moulded plastic housing 4 having a generally tubular body portion 5 and an integral flange portion 6 formed with screw holes 7 for attachment to the edge face of a door so that the roller axis is vertical. The moulded plastic keeper plate 8 formed with screw holes 9 for mounting on the corresponding jamb post has a rectangular recess 10 defining an aperture in which the roller 3 engages when the door is closed.

As can be seen from FIGURE 1 the roller 3 has a barrel-shaped outer surface to provide a self-aligning action, and the keeper 8 has a projecting tongue 12 which tapers to provide a ramp up which the roller 3 rolls prior to entering the recess 10.

A guide aperture 13 through which the roller 3 projects is formed in the flange portion 6 with upper and lower edges which engage the corresponding edges of the fork limbs 2 to guide the latter during operative movement of the plunger 1. The plunger 1 has a stem 14 which projects through and is guided in a central bore 15 in an inner end wall 16 of the housing 4.

Over a portion of its length immediately adjacent the flange portion 6 the body portion 5 has aligned upper and lower slots 17, and thickened portions 18 of the fork limbs 2 respectively project through these slots and provide abutment shoulders 19 which engage the rear surface of the flange portion 6 to prevent excessive outward projection of the plunger 1. The wall of the housing 4 has parallel side grooves 20 to provide bearing surfaces which engage corresponding side portions on the fork limbs 2 to assist in guiding the plunger 1 during its operative movement, and these grooves 20 accept the roller 3 during inward movement of the latter. A compression spring 22 around the stem portion 14 of the plunger 1 urges the latter outwardly from the housing 4.

Adjustment means are provided so that the normal outward projection of the plunger 1, and hence of the roller 3, can be decreased if necessary, and these means comprise a self-locking nut 23 threaded on the projecting end of the stem portion 14. The nut 23 abuts the housing end Wall 16 when the plunger is in the outermost position.

During assembly of the catch the plunger 1, with the roller 3 sprung into position between the limbs 2, is inserted into the housing through the guide aperture 13. The thickened portions 18 of the fork limbs 2 are pro vided with a lead at 24 so that the abutment shoulders 19 automatically clear the aperture 13 by relative inward flexing of the forkk limbs 2 and spring outwardly into position behind the flange portion 6 to limit outward projection of the plunger 1 and roller 3.

The arrangement of FIGURES 1 to 4 and the modification of FIGURE differ only in the manner in which the fork limbs 2 are provided with clearance relatively to the roller 3 to allow inward flexing during assembly without providing an excessive end float of the roller 3. In the first arrangement the limbs 2 are cut away inwardly of the pivot of the roller 3 at 25, so that the roller 3 is a good fit between the outer ends of the limbs 2 but the latter can flex sufficiently about the pivot to allow the abutment shoulders 19 to clear the aperture 13 during assembly. The inner surfaces 25 of the limbs 2 in this case remain parallel.

In the modification of FIGURE 5 the clearance is provided by a continuous taper of the inner surfaces 26 of the limbs 2 from the outer end of the latter. This simplifies the moulding procedure to some extent and enables less clearance to be left as the limbs 2 during assembly flex about the outer ends of the limbs.

The described formation of the housing 4 is of particular advantage from the moulding standpoint in that it enables a cylindrical mould to be used with two side plates against which a moulding core engages, to this end the distance between said upper and lower edges of the guide aperture 13 being made equal to the depth of the body portion 5. As a result, withdrawal of the core after moulding occurs along the laterally moulded slots 26 in the body portion 5 so that all moulding is accomplished with a single direction of core withdrawal.

A marked advantage of the described constructions, as compared with previous all-metal forms of roller catches, is the freedom from corrosion which affects the operation of previous arrangements adversely when they are used in adverse atmospheric conditions, particularly in outdoor applications.

I claim:

1. A roller catch comprising a housing adapted to be mounted at the edge of a door, the outer end of the housing having an aperture, a plunger slidably mounted within said housing with a forked outer end projecting from said housing aperture, a roller rotatably mounted between the fork limbs of said plunger, and spring means urging the plunger outwardly from said housing, said plunger being manufactured from a resilient plastic material and formed with an abutment shoulder adjacent said forked end which engages the housing to prevent excessive outward projection of the plunger therefrom and the fork limbs being sufficiently flexible to allow the plunger during assembly to be sprung into position in the housing through said aperture whereupon the plunger is retained within the housing by said shoulders.

2. A roller catch comprising a housing, a spring-loaded plunger urged by the spring loading to an outwardly projecting position relatively to said housing within which it is slidably mounted, a roller rotatably mounted between the limbs of a forked outer end of the plunger, said plunger being moulded from a resilient plastic material with an outwardly facing abutment shoulder on each fork limb arranged to engage the housing to limit the maximum possible outward projection of the plunger from the housing, said material being sufliciently flexible to allow the fork limbs to be flexed inwardly sufficiently to allow the plunger with the roller thereon to be sprung into position in the housing during assembly through the end of the latter from which it projects whereupon the plunger is retained within the housing by said shoulder.

3. A door catch according to claim 2, wherein the inner surfaces of the fork limbs are substantially parallel and cut away inwardly of the roller axis to provide a clearance relatively to the roller to facilitate flexing of the fork limbs during assembly.

4. A door catch according to claim 2, wherein the inner surfaces of the fork limbs taper outwardly from the outer ends of the limbs to provide a clearance relatively to the roller to facilitate flexing of the fork limbs during assembly.

5. A roller catch comprising a housing, a spring-loaded plunger urged by the spring loading to an outwardly projecting position relatively to said housing within which it is slidably mounted, a roller rotatably mounted between the limbs of a forked outer end of the plunger, said plunger being moulded from a resilient plastic material with an outwardly facing abutment shoulder on each fork limb arranged to engage the housing to limit the maximum posible outward projection of the plunger from the housing, said fork limbs being formed with clearance relatively to the roller inwardly of the rotational axis thereof and said material being sufiiciently flexible to allow the fork limbs to be flexed on assembly sufliciently to allow the plunger with the roller thereon to be sprung into position in the housing through the end of the latter from which it projects whereupon the plunger is retained Within the housing by said abutment shoulders.

6. A roller catch comprising a housing adapted to be mounted at the edge of a door and formed with an outer end aperture, a plunger slidably mounted within said housing with a forked outer end projecting through said housing aperture and a threaded inner end projecting through an inner end wall of said housing, a roller rotatably mounted between the fork limbs of said plunger, said plunger being manufactured from a resilient plastic material and formed with an abutment shoulder which engages the housing to prevent excessive outward projection of the plunger therefrom and the fork limbs being sufficiently flexible to allow the plunger during assembly to be sprung into position in the housing through said aperture whereupon the plunger is retained within the housing by said abutment shoulder, spring means urging the plunger outwardly from said housing, and a self-locking nut threaded on said inner end of the plunger for engagement with said inner end wall to limit the normal projection of said plunger from said housing and provide an adjustment for the degree of projection.

7. A roller catch comprising a tubular housing adapted to be mounted in the edge of a door and formed at the outer end with an attachment flange, a spring-loaded plunger slidably mounted within said housing and urged to a position in which it projects outwardly from the housing through a guide aperture at said outer end of the housing, said aperture having upper and lower edges which engage and guide the limbs of a forked outer end of the plunger, and a roller rotatably mounted between said fork limbs, said plunger being moulded with abutment means which engage the housing to limit outward projection of the plunger which is moulded from a resilient plastic material sufficiently flexible to allow the fork limbs to flex sufficiently for said abutment means to clear said guide aperture and allow the plunger to be sprung into position within said housing during assembly, whereupon said plunger is retained within said housing by said abutment means.

8. A roller catch comprising a tubular housing adapted to be mounted in the edge of a door, a spring-loaded plunger slidably mounted within said housing and urged to a position in which it projects outwardly from the housing through a guide aperture at the outer end of the housing, said aperture having upper and lower edges which engage and guide the limbs of a forked outer end of the plunger, and a roller rotatably mounted between said fork limbs, said plunger being moulded with outwardly facing abutment shoulders which engage the housing to limit outward projection of the plunger which is moulded from a resilient plastic material sufiiciently flexible to allow the fork limbs to flex sufliciently for said abutment shoulders to clear said guide aperture and allow the plunger to be sprung into position within said housing during assembly, whereupon said plunger is retained within said housing by said abutment shoulders.

9. A roller catch comprising a tubular housing adapted 'to be mounted in the edge of a door and moulded in flange, a spring-loaded plunger slidably mounted within said housing and urged to a position in which it projects outwardly from the housing through a guide aperture at said outer end of the housing, said aperture having upper and lower edges which engage and guide the limbs of a forked outer end of the plunger, and a roller rotatably mounted between said fork limbs, the limbs of said plunger being moulded with abutment shoulders which engage the housing to limit outward projection of the plunger which is moulded from a resilient plastic material sufiiciently flexible to allow the fork limbs to flex sufficiently for said abutment shoulders to clear said guide aperture and allow the plunger to be sprung into position within said housing during assembly, whereupon said plunger is retained within said housing by said abutment shoulders.

UNITED STATES PATENTS Herold Dec. 15, Ramsey et al May 2, Austin June 17, Gilman June 17, Robinson Feb. 13, Beil June 11, Hensel July 8, Sarro Mar. 24, Ahlgren July 26,

FOREIGN PATENTS Great Britain Nov. 21, 

1. A ROLLER CATCH COMPRISING A HOUSING ADAPTED TO BE MOUNTED AT THE EDGE OF A DOOR, THE OUTER END OF THE HOUSING HAVING AN APERTURE, A PLUNGER SLIDABLY MOUNTED WITHIN SAID HOUSING WITH A FORKED OUTER END PROJECTING FROM SAID HOUSING APERTURE, A ROLLER ROTATABLY MOUNTED BETWEEN THE FORK LIMBS OF SAID PLUNGER, AND SPRING MEANS URGING THE PLUNGER OUTWARDLY FROM SAID HOUSING, SAID PLUNGER BEING MANUFACTURED FROM A RESILIENT PLASTIC MATERIAL AND FORMED WITH AN ABUTMENT SHOULDER ADJACENT SAID FORKED END WHICH ENGAGES THE HOUSING TO PREVENT MAJOR FACE THEREOF A PLURALITY OF ROUNDED LOAD BEARING RIBS INTEGRAL THEREWITH, SAID ROUNDED RIBS BEING IN DIRECT LOAD BEARING ENGAGEMENT WITH ONE OF SAID MEMBERS FOR LUBRICATED SLIDING MOTION IN RESDPECT THERETO DURING SAID ROTARY MOTION AND EACH SPACE BETWEEN SAID RIBS DEFINING A LUBRICANT RECEIVING POCKET, LUBRICANT POCKET SEALING MEANS INTEGRAL WITH SAID RUBBER-LIKE BUSHING MEANS AND LOCATED WITHIN THE CONFINES OF SAID MEMBERS AND IN SEALING ENGAGEMENT WITH SAID ONE OF SAID MEMBERS WHEREBY LUBRICANT WITHIN EACH OF THE POCKETS IS SUBSTANTIALLY PERMANENTLY RETAINED WITHIN SAID POCKET, VISCOUS LUBRICANT LOCATED IN SAID POCKETS BETWEEN SAID RIBS WHEREBY UPON SAID ROTARY MOTION OF SAID BUSHING IN RESPECT TO SAID ONE MEMBER SAID LUBRICANT IN SAID POCKETS LUBRICATES THE ROUNDED LOAD BEARING RIBS, SAID ROUNDED RIBS PRESENTING NO SHARP EDGES TO THE LUBRICATED SURFACE OF SAID ONE MEMBER WHEREBY THERE IS NO WIPING ACTION WHICH SUBSTANTIALLY COMPLETELY REMOVES LUBRICANT FROM SAID LUBRICATED SURFACE. 